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BUG: KASAN: use-after-free in instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
BUG: KASAN: use-after-free in atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:252 [inline]
BUG: KASAN: use-after-free in __refcount_add include/linux/refcount.h:184 [inline]
BUG: KASAN: use-after-free in __refcount_inc include/linux/refcount.h:241 [inline]
BUG: KASAN: use-after-free in refcount_inc include/linux/refcount.h:258 [inline]
BUG: KASAN: use-after-free in sock_hold include/net/sock.h:781 [inline]
BUG: KASAN: use-after-free in sco_conn_del+0xa5/0x310 net/bluetooth/sco.c:199
Write of size 4 at addr ffff888062671080 by task syz-executor/7095

CPU: 0 UID: 0 PID: 7095 Comm: syz-executor Not tainted 6.12.0-rc1-syzkaller-00163-gb63c755cb65d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:488
 kasan_report+0x143/0x180 mm/kasan/report.c:601
 kasan_check_range+0x282/0x290 mm/kasan/generic.c:189
 instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
 atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:252 [inline]
 __refcount_add include/linux/refcount.h:184 [inline]
 __refcount_inc include/linux/refcount.h:241 [inline]
 refcount_inc include/linux/refcount.h:258 [inline]
 sock_hold include/net/sock.h:781 [inline]
 sco_conn_del+0xa5/0x310 net/bluetooth/sco.c:199
 hci_disconn_cfm include/net/bluetooth/hci_core.h:1975 [inline]
 hci_conn_hash_flush+0xff/0x240 net/bluetooth/hci_conn.c:2589
 hci_dev_close_sync+0x9ef/0x11a0 net/bluetooth/hci_sync.c:5195
 hci_dev_do_close net/bluetooth/hci_core.c:483 [inline]
 hci_unregister_dev+0x20b/0x510 net/bluetooth/hci_core.c:2698
 vhci_release+0x80/0xd0 drivers/bluetooth/hci_vhci.c:664
 __fput+0x23f/0x880 fs/file_table.c:431
 task_work_run+0x24f/0x310 kernel/task_work.c:228
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0xa2f/0x28e0 kernel/exit.c:939
 do_group_exit+0x207/0x2c0 kernel/exit.c:1088
 __do_sys_exit_group kernel/exit.c:1099 [inline]
 __se_sys_exit_group kernel/exit.c:1097 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1097
 x64_sys_call+0x2634/0x2640 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f703237dff9
Code: Unable to access opcode bytes at 0x7f703237dfcf.
RSP: 002b:00007ffc783632c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f703237dff9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000043
RBP: 00007f70323dd588 R08: 00007ffc78361067 R09: 0000000000000003
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000003 R14: 00000000ffffffff R15: 00007ffc78363470
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x8 pfn:0x62671
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 0000000000000000 ffffffffffffffff 0000000000000000
raw: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4684, tgid 4684 (udevd), ts 194248591082, free_ts 206675022469
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1537
 prep_new_page mm/page_alloc.c:1545 [inline]
 get_page_from_freelist+0x3045/0x3190 mm/page_alloc.c:3457
 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4733
 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265
 alloc_slab_page+0x6a/0x120 mm/slub.c:2413
 allocate_slab+0x5a/0x2f0 mm/slub.c:2579
 new_slab mm/slub.c:2632 [inline]
 ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3819
 __slab_alloc+0x58/0xa0 mm/slub.c:3909
 __slab_alloc_node mm/slub.c:3962 [inline]
 slab_alloc_node mm/slub.c:4123 [inline]
 kmem_cache_alloc_noprof+0x1c1/0x2a0 mm/slub.c:4142
 getname_flags+0xb7/0x540 fs/namei.c:139
 getname fs/namei.c:225 [inline]
 __do_sys_unlink fs/namei.c:4581 [inline]
 __se_sys_unlink fs/namei.c:4579 [inline]
 __x64_sys_unlink+0x3a/0x50 fs/namei.c:4579
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 2870 tgid 2870 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1108 [inline]
 free_unref_page+0xcfb/0xf20 mm/page_alloc.c:2638
 discard_slab mm/slub.c:2678 [inline]
 __put_partials+0xeb/0x130 mm/slub.c:3146
 put_cpu_partial+0x17c/0x250 mm/slub.c:3221
 __slab_free+0x2ea/0x3d0 mm/slub.c:4450
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:247 [inline]
 slab_post_alloc_hook mm/slub.c:4086 [inline]
 slab_alloc_node mm/slub.c:4135 [inline]
 kmem_cache_alloc_node_noprof+0x16b/0x320 mm/slub.c:4187
 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:668
 alloc_skb include/linux/skbuff.h:1322 [inline]
 nlmsg_new include/net/netlink.h:1015 [inline]
 rtmsg_ifa+0x1f0/0x3b0 net/ipv4/devinet.c:1932
 __inet_del_ifa+0x870/0x1040 net/ipv4/devinet.c:446
 inet_del_ifa net/ipv4/devinet.c:484 [inline]
 inetdev_destroy net/ipv4/devinet.c:337 [inline]
 inetdev_event+0x6a5/0x1550 net/ipv4/devinet.c:1628
 notifier_call_chain+0x19f/0x3e0 kernel/notifier.c:93
 call_netdevice_notifiers_extack net/core/dev.c:2034 [inline]
 call_netdevice_notifiers net/core/dev.c:2048 [inline]
 unregister_netdevice_many_notify+0xedd/0x1da0 net/core/dev.c:11403
 unregister_netdevice_many net/core/dev.c:11465 [inline]
 default_device_exit_batch+0xa1f/0xaa0 net/core/dev.c:11948
 ops_exit_list net/core/net_namespace.c:178 [inline]
 cleanup_net+0x89d/0xcc0 net/core/net_namespace.c:626

Memory state around the buggy address:
 ffff888062670f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888062671000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888062671080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff888062671100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888062671180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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